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	<title>Document</title>
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	<script type="text/javascript">
		//提示用户输入几天后
		var day = parseInt(prompt("请输入几天后"));
		//然后计算。本题有很多算法，只要正确就可以咯。
		//var xingqi = (6 + day % 7) % 7;
		var xingqi = (6 + day) % 7
		//输出
		alert(day + "天后的星期是" + xingqi);
	</script>
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